Analog noise generator

Abstract

The present invention relates to a device for producing an analog noise from a point process, the distribution of said noise being predeterminable, said device comprising a source of noise, a first generator or random pulse generator, a second generator or motif or function generator, the output of the source of noise being connected to the input of the first generator, the output of the first generator being connected to the input of the second generator, and the output of the second generator constituting the output of the whole of said device. The invention is applicable to the coding and transmission of information.

What we claim is: 
     
       1. A device for generating an analog noise from a point process, the distribution of said noise being predeterminable, said device comprising: a first generator assembly generating a sequence of random pulses;   a second generator assembly comprising an integrator RC circuit supplied by a D.C. source, said RC circuit having a capacitor shunted by a controlled switch having a control electrode;   means for applying said sequence of random pulses to said control electrode, said controlled switch taking the ON state during each of said random pulses; and   means for picking up said analog noise from a point between the resistor and the capacitor of said RC circuit.   
     
     
       2. A device according to claim 1, wherein said first generator assembly comprises: a physical noise source; and   a comparator circuit with two inputs, one of which is supplied by said physical noise source and the other of which is supplied by a circuit establishing a threshold, said comparator circuit supplying a pulse each time the level of said physical noise exceeds said threshold, whereby said sequence of random pulses is produced.   
     
     
       3. A device according to claim 2, wherein said threshold circuit comprises: an averaging circuit having an input which is connected to a point between the resistor and the capacitor of said RC circuit;   a variation amplifier having two inputs, one of which is connected to the output of said averaging circuit and the other of which is connected to a DC source of a predetermined magnitude;   and means connecting the output of said variation amplifier to an input of said comparator circuit.   
     
     
       4. A device according to claim 1, wherein said first generator assembly comprises: a shift register having an input and a plurality of outputs;   a binary random noise source having an output connected to an input of said shift register;   an AND gate having an output and a plurality of inputs, said inputs being connected to the outputs of said shift register; and   a clock for synchronizing said shift register;   the output of said AND gate being connected to said control electrode, said controlled switch taking the ON state during each of the pulses produced by said AND gate.